Dual pointing device used to control a cursor having absolute and relative pointing devices

ABSTRACT

A personal computer system enables simultaneous use of a relative-coordinate-mode input device and an absolute-coordinate-mode input device, thereby allowing correct input of absolute coordinate data, such as for characters. A pad-type first input device and a stick-type second input device are provided for a notebook computer. The first input device outputs both absolute coordinate data and relative coordinate data. The second input device outputs only relative coordinate data. When the absolute coordinate data is output, the relative coordinate data format is converted into the same format as the absolute coordinate data, and ID information for distinguishing the relative coordinate data from the absolute coordinate data is added to part of the relative coordinate data format.

This application is a continuation of U.S. Application Ser. No.09/471,837 filed Dec. 23, 1999, entitled “Dual Pointing Screen CursorDevice Comprising Touch Pad and Stick Wherein Each Has Identifying BytesThat is Transmitted Through Single Channel Port,” and is now U.S. Pat.No. 6,681,268, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a personal computer system that allowsinformation input from different types of input devices, such as apad-type input-device and a pointing-stick-type (hereinafter simplyreferred to as the “stick-type”) input device, both of which areintegrated into a notebook computer, to be processed by using software.

2. Description of the Related Art

As conventional input devices (controllers) for use in notebookcomputers, pad-type input devices and stick-type input devices are used.

In a pad-type input device, a quadrilateral flat pad is disposed in thevicinity of a keyboard, and a user slides a finger on the pad so as toinput information to move a pointer (mouse cursor) displayed on thescreen in the X- and Y-axis directions (i.e., in the plane of thescreen). By tapping a finger on the pad, Z-axis information can also beinput.

In a stick-type input device, a small-diameter stick is disposed in thevicinity of the center of a keyboard, and a user tilts the stick with afinger in a desired direction so as to input information for moving apointer displayed on the screen in the X- and Y-axis directions.

By using the pad-type input device, both relative coordinate data andabsolute coordinate data can be output to a computer. By using thestick-type input device, only relative coordinate data is output to acomputer. The relative-coordinate-data input mode is used for moving acursor on the computer screen, while the absolute-coordinate-data inputmode is used for moving the cursor or manually writing characters,graphics, etc.

Generally, as shown in FIG. 4, the relative coordinate data handled foreach type of input device is processed by a three-byte format signal.The first-byte field indicates the overflow bit (YO, XO), the sign bit(YS, XS), button information, etc. The second- and third-byte fieldsrepresent X-coordinate and Y-coordinate variable information formed ofthe X count and the Y count, respectively.

The absolute coordinate data is processed, as illustrated in FIG. 5, bya six-byte format signal. The first-byte field designates ID informationfor distinguishing the corresponding input device from an external inputdevice (for example, a mouse). The second-, third-, fourth-, fifth-, andsixth-byte fields respectively indicate the X count, the X count andbutton information, the Y count and button information, the Y count, andthe Z count.

However, in the above-described conventional personal computer system,the two types of input devices, such as the pad-type input device andthe stick-type input device, cannot be easily used in combination, whichcauses the following problems.

To input absolute coordinate data by using the pad-type input device(for example, to write characters, such as signatures), a user slides afinger or a pen on the pad. In this case, once the user lifts the fingeror the pen away from the pad at the intersection of lines forming acharacter, the user may not be able to recognize the position from whichthe user should begin writing the next stroke. This may disturb thebalance of the character or make the character illegible, and the usermay thus be required to input the character again.

As stated above, conventional pad-type input devices have been employedfor inputting characters. However, the resulting operation-data formatsignals differ between relative coordinate data and absolute coordinatedata. Accordingly, a switching operation between therelative-coordinate-data input mode and the absolute-coordinate-datainput mode is required. For example, when the user loses track of theinput position while operating in the absolute-coordinate-data inputmode, the user switches to the relative-coordinate-data input mode. Inthis case, specific software is required for switching between therelative coordinate data and the absolute coordinate data, and in somecases, the computer must be restarted, thereby reducing ease ofoperation.

SUMMARY OF THE INVENTION

Accordingly, in order to solve the above-described problems, it is anobject of the present invention to provide a personal computer systemthat allows relative coordinate data and absolute coordinate data to beused simultaneously without the need for a switching operation.

It is another object of the present invention to provide a personalcomputer system that allows a relative-coordinate-data input device andan absolute-coordinate-data input device to have the same type of signalformat so as to simplify signal processing in response to an input froman input device and also to easily distinguish between the two types ofinput devices.

In order to achieve the above-described objects, according to one aspectof the present invention, there is provided a personal computer systemincluding a plurality of different types of coordinate input devices, akeyboard input device, an output device for outputting a signal fromeach of the coordinate input devices, and a processing unit forperforming processing based on signals from the output device inaccordance with an operation of each of the coordinate input devices. Asingle output port of the output device is shared by the coordinateinput devices.

According to another aspect of the present invention, there is provideda personal computer system including a first input device, a secondinput device, the second input device performing a detecting operationin a manner differing from the first input device, a keyboard inputdevice, and an output device for converting one of an output signal fromthe first input device and an output signal from the second inputdevice, or for converting both the output signals from the first inputdevice and from the second input device and outputting the resultingsignals in an identical format. Thus, the first input device and thesecond input device are alternately or simultaneously used.

In the aforementioned personal computer system, the first input devicemay output absolute coordinate data and/or relative coordinate data, andthe second input device may output relative coordinate data.

The first input device may be a pad-type input device disposed closer toan operator than the keyboard input device, and the second input devicemay be a stick-type input device disposed between keys of the keyboardinput device.

According to a further aspect of the present invention, there isprovided a personal computer system including a first input device, asecond input device, an output device for outputting operation signalsfrom the first input device and from the second input device in anidentical signal format, and a processing unit for performing processingbased on the signal supplied from the output device in accordance withan operation of each of the first input device and the second inputdevice. The output device adds identification (ID) information to partof the signal format according to the type of input device.

According to the present invention, a plurality of different types ofcoordinate input devices are provided, and the single output port of theoutput device is shared by the plurality of input devices. Thus, thestructure of the output port is simple, and output signals from theoutput port can be in the same format. As a consequence, only a singleprocessing unit is required for the plurality of coordinate inputdevices.

In the present invention, the first input device and the second inputdevice employing different detecting operation modes, and the keyboardinput device are provided for the personal computer system. Thedifferent types of input devices can be simultaneously used without theneed for a switching operation. Accordingly, the first and second inputdevices are suitably used in combination according to the purpose of useand operability of the individual devices, thereby improving ease ofoperation.

The first input device outputs absolute coordinate data and/or relativecoordinate data, thereby enabling signatures, characters, etc. to beinput. The first input device also outputs X- and Y-axis relativecoordinate data. The second input device only outputs X- and Y-axisrelative coordinate data. Thus, the type of data to be input can beselected according to the operating use.

Additionally, as discussed above, the first input device, which servesas a pad-type input device, is disposed closer to an operator than thekeyboard input device, while the second input device, which serves as astick-type input device, is disposed between keys of the keyboard inputdevice, thereby further enhancing the operating use.

By using different types of input devices integrated into, for example,a notebook computer, the user is able to simultaneously performoperations without having to switch between the input devices. In thiscase, when the two different types of input devices are usedsimultaneously, the processing in the processing unit having a built-indevice driver becomes complicated unless the signals having the sameformat are output from the output device. It is also difficult todistinguish between the output signals supplied from the different inputdevices. Accordingly, in the present invention, ID information is addedto part of the signal format output from one of the input devices so asto distinguish between the signals output from the two input devices.

In the present invention, the first input device may output variableinformation on X, Y, and Z three-dimensional coordinates, and the secondinput device may output variable information on X and Y two-dimensionalcoordinates. In using the second input device, fixed information may beadded to a Z-information field of the signal format output from theoutput device. In this case, the processing unit may process the X, Y,and Z information as absolute coordinate data and X and Y information asrelative coordinate data.

For example, the output device may generate six-byte absolute coordinatedata and may supply it to the processing unit in response to thevariable information on the X, Y, and Z three-dimensional coordinatessupplied from the first input device. The output device may convertthree-byte displacement data into six-byte data in response to thevariable information on the X and Y two-dimensional coordinates suppliedfrom the second input device, and fixed information may be added to aZ-information field of the converted six-byte data.

More specifically, the individual byte fields of the six-byte datasupplied from the output device to the processing unit may respectivelyindicate the identification information, X count information, X countand button information, Y count and button information, Y countinformation, and Z count information. The Z-count information may becomevariable in accordance with an operation of the first input device inresponse to the variable information supplied from the first inputdevice, and the Z-count information may become fixed in response to thevariable information supplied from the second input device.

With this arrangement, the three-byte format of the relative coordinatedata is converted into the six-byte format in the output device, whichappears to be the same format as the absolute coordinate format, and isthen sent to the processing unit. In this case, there is no need to fillcoordinate data in the Z-axis data field of the relative coordinate dataformat. Thus, ID information for distinguishing the relative coordinatedata from the absolute coordinate data is filled in the Z-axis datafield. If the Z-axis data field is used normally from 00h through 7Fh,00h through 7Eh are assigned to the variable information of the absolutecoordinate data, and the remaining 7Fh is allocated to the IDinformation of the relative coordinate data. Thus, when the 7Fh data isoutput from the output device and is sent to the device driver of theprocessing unit, it can be determined that the coordinate data has beensupplied from the input device that outputs only X- and Y-axis variableinformation.

The absolute coordinate data and the relative coordinate data can beoutput by using, for example, a pad-type input device, and the relativecoordinate data can be output by using, for example, a stick-type inputdevice. In the pad-type input device, signatures, characters, and so on,can be input by using a finger or a pen on the pad surface, i.e., theabsolute coordinate data can be output according to the path of dotdata. The X- and Y-axis relative coordinate data (displacement data) canalso be output by sliding a finger on the pad surface. In the stick-typeinput device, the stick-type operator is tilted in a desired directionso as to output X- and Y-axis relative coordinate data.

By outputting the relative coordinate data, the pointer (cursor)displayed on the display unit can be moved in a desired direction. Incontrast, in the absolute-coordinate-input mode, a desired regiondisplayed on the display unit can be selected. By outputting theabsolute coordinate data, signature authentication, such as forcharacter input, can be performed.

Moreover, both types of input devices can be used simultaneously, andwhen they are in the relative-coordinate-input mode, the user is able touse both the input devices without the need for a switching operation.Even when both the relative-coordinate-data mode and theabsolute-coordinate-data mode are employed, the user is able to use boththe input devices without the need for a switching operation. In thiscase, when both types of input devices are used simultaneously in thetwo modes, output coordinate data are alternately sent to the driverprovided for the processing unit, and predetermined processing isperformed on the data.

In conducting character input by sliding a finger or a pen on the padsurface by using a pad-type input device, once the user lifts the fingeror the pen from the pad surface, the user may not be able to recognizethe input position. In this case, the user operates the stick-type inputdevice to move the pointer to the position at which the user stoppedwriting, and then continues writing the characters. As a consequence,the characters can be input correctly.

The output device may include a switching portion for switching betweena path for converting the variable information obtained from the secondinput device into the six-byte data and a path for outputting thevariable information as three-byte data.

With this configuration, when relative coordinate data is output formboth the first and second input devices, the data from the second inputdevice is processed by the three-byte format and is sent to theprocessing unit.

In the aforementioned personal computer system of the present invention,not only a combination of two input devices, such as a pad-type inputdevice and a stick-type input device, but also a mouse-type input devicemay be connected as an external device. All the data from the threeinput devices are processed by a driver provided for the processingunit. In this case, characters may be input into the pad-type inputdevice to output absolute coordinate data. Scroll data may be input intothe stick-type input device to vertically and horizontally scroll anediting screen of a word processor or a spreadsheet. Relative coordinatedata may be output from the mouse-type input device to move the pointer(cursor) on the screen.

The position and content of the ID information may be changed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating the external appearance of anotebook computer incorporating a personal computer system according toan embodiment of the present invention;

FIG. 2 is a block diagram illustrating the circuit configuration of anembodiment of the present invention;

FIG. 3 is a flow chart illustrating the operation performed by a devicedriver when the personal computer system shown in FIG. 1 is used;

FIG. 4 schematically illustrates the data arrangement processed by athree-byte format; and

FIG. 5 schematically illustrates the data arrangement processed by asix-byte format.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention is described below with referenceto the drawings.

Referring to the perspective view of a notebook computer shown in FIG.1, a personal computer system generally indicated by 1 is integratedinto the notebook computer. More specifically, a keyboard 6 is disposedon the upper surface of a housing 8. A first input device 2 using aquadrilateral flat pad-type sensor 2 a (FIG. 2) is disposed at theproximal side adjacent to the keyboard 6. A second input device 3 usinga stick-type distortion sensor 3 a (FIG. 2) is provided in the vicinityof the center of the keyboard 6. Button switches 4 and 4 arehorizontally disposed separately from the first input device 2 at theproximal side.

Only relative coordinate data is input by using the second input device3, while both relative coordinate data and absolute coordinate data areinput by using the first input device 2. The first input device 2 may beof an electrostatic capacitive type or a pressure-sensing type.

A display unit 5, which is formed of a pivotable liquid crystal panel,is attached to the housing 8. When the first input device 2 is used, therelative coordinate data for shifting a pointer (cursor) 7 indicated onthe display unit 5 can be input by sliding a finger or a pen on the padsurface. When the second input device 3 is used, the above relativecoordinate data can be input by pressing the head of the stick with afinger in a desired direction. Additionally, by using the first inputdevice 2, signatures, characters, graphics, etc., can be written on thepad surface, so that the path of the signatures, characters, graphics,etc., are input as absolute coordinate data and are displayed on thedisplay unit 5.

Referring to the block diagram shown in FIG. 2, the personal computersystem 1 is formed of the first input device 2, the second input device3, and a host personal computer (host PC) 26. The distortion sensor 3 a,which serves as a stick-type input device, the sensor 2 a, which servesas a pad-type input device, and the related elements other than hardwaremay be formed by an electronic circuit built into the housing 8.Alternatively, the above-described elements, other than the inputdevices, may be integrated into the host PC 26 as software. The inputdevices and the related elements other than hardware correspond to anoutput device of the present invention, a device driver built into thehost PC 26 corresponds to a processing unit of the present invention.

The first input device 2 and the second input device 3 are connected toeach other via interfaces 14 and 24. The host PC 26 is connected to thesecond input device 3 via an interface 25. With this arrangement, outputdata of the first input device 2 and output data of the second inputdevice 3 are output from a single output port 25 a of the interface 25,and there is no need to provide processing units separately for thefirst input device 2 and the second input device 3. In other words, thedevice driver of the host PC 26 serves as a shared processing unit forprocessing signals from both the first input device 2 and the secondinput device 3. The signals processed by the device driver undergofurther predetermined processing by an operating system (OS) so as to beconverted into signals to be output to the display unit 5.

The first input device 2 is provided with the sensor 2 a, which servesas a pad-type input device, for detecting the contact of a finger or apen with the pad surface, and a coordinate detector 2 b for detectingthe contact position of the finger or the pen.

The first input device 2 is also provided with a relative displacement(coordinate) converter 11 a for converting operation data into relativecoordinate data, and with an absolute coordinate converter 11 b forconverting operation data into absolute coordinate data, both converters11 a and 11 b being connected in parallel to the coordinate detector 2b. The relative displacement converter 11 a and the absolute coordinateconverter 11 b are connected to the interface 14. A three-byte/six-byteformat switching controller 12 is also connected to the interface 14 soas to control via an inverter 13 a switch 12 a disposed between therelative displacement converter 11 a and the coordinate detector 2 b anda switch 12 b provided between the absolute coordinate converter 11 band the coordinate detector 2 b.

In response to a command from the host PC 26, the format switchingcontroller 12 switches between the input operation for inputtingthree-byte relative coordinate data shown in FIG. 4 by using the sensor2 a and the input operation for inputting six-byte absolute coordinatedata shown in FIG. 5 by using the sensor 2 a. When relative coordinatedata is input from the coordinate detector 2 b, the switch 12 a isturned on and the switch 12 b is turned off. Conversely, when theabsolute coordinate data is input from the coordinate detector 2 b, theswitch 12 b is turned on and the switch 12 a is turned off.

The second input device 3 includes the distortion sensor 3 a, whichserves as a stick-type input device, for detecting distortion of thestick, and a distortion detector 3 b for detecting the amount ofdistortion. A value obtained from the distortion detector 3 b isconverted into relative displacement data by a relative displacement(coordinate) converter 3 c.

The relative displacement converter 3 c is connected to a sum counter 15and a three-byte format converter 16. Relative displacement datasequentially input from the relative displacement converter 3 c isaccumulated in the sum counter 15, and is converted into the three-byterelative coordinate data format shown in FIG. 4 by the format converter16. The data is then sent to the device driver of the host PC 26 via theinterface 25, and predetermined processing is executed on the data.

The relative displacement converter 3 c is also connected to athree-byte buffer 21 a and to a six-byte format converter 22 a. Therelative displacement data supplied from the relative displacementconverter 3 c is temporarily stored in the buffer 21 a. The relativedisplacement data is then converted into the six-byte relativecoordinate data shown in FIG. 5 by the format converter 22 a, and an IDflag, which serves as ID information, is added to part of the six-byteformat. When the circuit of a device selector 23 is closed, the six-byterelative coordinate data is sent to the host PC 26 from the formatconverter 22 a via the interface 25.

The relative displacement data supplied from the relative displacementconverter 11 a of the first input device 2 is sent to the interface 24via the interface 14 and passes through a device selector 20 and the sumcounter 15 via a line L2. As a result, the relative displacement data issent to the three-byte format converter 16.

Meanwhile, the absolute coordinate data sent to the interface 24 fromthe absolute coordinate converter 11 b of the first input device 2 istemporarily stored in the six-byte buffer 21 b and is converted into thesix-byte format illustrated in FIG. 5 by a format converter 22 b. Whenthe device selector 23 is actuated, the six-byte-format absolutecoordinate data is sent to the host PC 26 from the buffer 21 b via theinterface 25.

Switches 17 a, 17 b, and 17 c are respectively provided for a line L0for connecting the relative displacement converter 3 c of the secondinput device 3 and the sum counter 15, a line L1 for connecting therelative displacement converter 3 c and the three-byte buffer 21 a, anda line L3 for connecting the first input device 2 and the six-bytebuffer 21 b via the interface 24. The switch 17 a is controlled by athree-byte/six-byte format switching controller 17, while the switches17 b and 17 c are controlled by the format switching converter 17 via aninverter 18.

According to the personal computer system 1 configured as describedabove, relative coordinate data both from the pad-type sensor 2 a andfrom the stick-type distortion sensor 3 a can be sent to the host PC 26as the three-byte-format relative coordinate data illustrated in FIG. 4.Moreover, both absolute coordinate data from the pad-type sensor 2 a andrelative coordinate data from the stick-type sensor 3 a can be suppliedto the host PC 26 as the six-byte format signal shown in FIG. 5.

It may be determined by using dedicated software whether the data is tobe converted into the three-byte format or the six-byte format orwhether the data input from the pad-type sensor 2 a is to be handled asrelative coordinate data or absolute coordinate data. Alternatively, thekeyboard 6 may be used to directly input the selection.

When both the data input from the pad-type sensor 2 a and the data inputfrom the stick-type distortion sensor 3 a are used as three-byte-formatrelative coordinate data, the format switching controller 17 changes theswitches 17 a, 17 b, and 17 c so that the first input device 2 and thesecond input device 3 execute only three-byte format processing. Thatis, the format switching controller 17 controls the switch 17 a to beturned on and the switches 17 b and 17 c to be turned off via theinverter 18.

In this case, a switching signal is transmitted to the format switchingcontroller 12 from the host PC 26 via the interface 25, the line L4, theinterface 24, the interface 14, and a line L6, thereby turning on theswitch 12 a and the turning off the switch 12 b. Accordingly, data(relative coordinate data) obtained by the operation of the sensor 2 aof the first input device 2 is supplied to the relative displacementconverter 11 a and is converted into the relative coordinate data. Therelative coordinate data is then sent to the interface 24 of the secondinput device 3 via the interface 14.

The device selector 20 selects between the relative displacement dataconverted from the amount of displacement by the relative displacementconverter 3 c after being detected by the distortion sensor 3 a, and therelative displacement data sent from the relative displacement converter11 a via the line L2. More specifically, when the device selector 20 isswitched to P1, the relative displacement data from the pad-type sensor2 a is supplied to the sum counter 15. When the device selector 20 isswitched to P2, the relative displacement coordinate data from thestick-type distortion sensor 3 a is supplied to the sum counter 15. Thedevice selector 20 is switched to either the P1 or the P2 side under thecontrol of the host PC 26 according to whether the sensor 2 a or 3 a isoperated. Alternatively, the selector 20 may be alternately and rapidlyswitched to the P1 and P2 sides, and the relative displacement data maybe supplied to the sum counter 15 every time the pad-type sensor 2 a orthe stick-type distortion sensor 3 a is used.

The displacement values added in the sum counter 15 are converted intothe three-byte format shown in FIG. 4 by the three-byte format converter16, and the resulting signal is sent to the host PC 26 via the interface25. A device driver specifically used for the input devices 2 and 3 isprovided for the host PC 26, and the OS executes predeterminedprocessing based on the relative coordinate data sent to the devicedriver, thereby shifting the pointer 7 displayed on the display unit 5(see FIG. 1).

When the first input device 2 is used as an absolute-coordinate inputdevice, both input signals from the first input device 2 and from thesecond input device 3 are supplied to the host PC 26 as the six-byteformat data shown in FIG. 5.

In this case, the format switching controller 17 controls the switch 17a to be off and the switches 17 b and 17 c to be on via the inverter 18.The format switching controller 12 of the first input device 2 controlsthe switch 12 a to be off and the switch 12 b to be on.

Consequently, coordinate information detected by the coordinate detector2 b according to the operation of the sensor 2 a of the first inputdevice 2 is converted into absolute coordinate data by the absolutecoordinate converter 11 b. The absolute coordinate data is then sent tothe interface 24 of the second input device 3 via the interface 14, andis supplied to and is stored in the six-byte buffer 21 b via the lineL3. Subsequently, the absolute coordinate data is converted into thesix-byte-format absolute coordinate data illustrated in FIG. 5 by theformat converter 22 b.

The amount of distortion detected by the distortion detector 3 b of thesecond input device 3 according to the operation of the distortionsensor 3 a is temporarily converted into relative displacement data bythe relative displacement converter 3 c. After the relative displacementdata is stored in the three-byte buffer 21 a, it is converted into thesix-byte-format relative coordinate data shown in FIG. 5 by the formatconverter 22 a. The format converter 22 a further adds an ID flag, as IDinformation for identifying the relative coordinate data, to part of thesix-byte format data.

The device selector 23 selects between the absolute coordinate databased on the input operation of the first input device 2 supplied fromthe format converter 22 b and the relative coordinate data based on theinput from the second input device 3 converted by the format converter22 a and added with the ID information. This selecting operation isperformed by switching the device selector 23 to either the P3 or the P4side in response to a command from the host PC 26 according to whetherthe sensor 2 a or the distortion sensor 3 a is used.

Alternatively, if both the first input device 2 and the second inputdevice 3 are used, the device selector 23 is alternately and rapidlyswitched to the P3 and P4 sides.

Accordingly, regardless of whether the sensor 2 a or the distortionsensor 3 a is used, the same six-byte format data is supplied to thedevice driver of the host PC 26.

The three-byte-format relative coordinate data converted by thethree-byte format converter 16 is shown in FIG. 4. The first-byte fieldindicates the overflow bit (YO, XO), the sign bit (YS, XS), buttoninformation, etc. The second- and third-byte fields representX-coordinate and Y-coordinate variable information formed of the X countand the Y count, respectively.

The six-byte-format coordinate data converted by the format converter 22a or 22 b is shown in FIG. 5. The first-byte field designates IDinformation for distinguishing the corresponding input device from anexternal input device (for example, a mouse), and the second-, third-,fourth-, fifth-, and sixth-byte fields indicate the X count, the X countand button information, the Y count and button information, the Y count,and the Z count, respectively.

Concerning the absolute coordinate data converted by the formatconverter 22 b, the Z count in a data field 30 becomes variable. Incontrast, regarding the relative coordinate data converted by the formatconverter 22 a, the Z count in the data field 30 becomes fixed (IDflag).

When the personal computer system 1 is operating to form the six-byteformat, both the relative coordinate data obtained by the operation ofthe distortion sensor 3 a and the absolute coordinate data obtained bythe operation of the sensor 2 a are supplied to the device driver of thehost PC 26 in the same six-byte signal format. It is thus easy toprocess both types of data in the device driver. The relative coordinatedata can be distinguished from the absolute coordinate data by checkingwhether the Z-count data field 30 represents an ID flag.

The operation of the device driver provided for the host PC 26 isdiscussed below with reference to the flow chart of FIG. 3.

In step ST1, data supplied from the interface 25 and data supplied froma third input device are decoded in the device driver. The third inputdevice may be a mouse controller externally connected to the notebookpersonal computer shown in FIG. 1. The structure of the third inputdevice is, for example, as follows. A sphere is disposed at the lower(or upper) portion of a housing, and two X- and Y-axis bars in contactwith the sphere are provided. The housing is moved in a desireddirection to rotate the sphere, and the corresponding rotational forceis detected by a detector formed of an encoder or the like. The mousecontroller is used for inputting relative coordinates.

Referring again to FIG. 3, it is determined in step ST2 whether thedecoded data is six-byte-format data. If the outcome of step ST2 is no,the data is processed as three-byte-format data in step ST8. Thisprocessing is executed when the circuit shown in FIG. 2 is operating togenerate three-byte-format data, or when the third input device, such asa mouse, is operating. According to the processing executed in step ST8,the data is processed as displacement data (tracking data) for shiftinga cursor (pointer) on the screen.

If it is found in step ST2 that the data is six-byte-format data, it isfurther determined in step ST3 whether the Z-count field indicates fixeddata (ID flag). If the ID flag is detected in step ST3, it is determinedthat the data is relative coordinate data supplied from the second inputdevice 3, and is processed as six-byte-format data in step ST7. If theID flag is not detected in step ST3, it is determined that the data isabsolute coordinate data supplied from the first input device 2, and isprocessed as six-byte-format data in step ST4. This data is obtained bywriting a signature, characters, or graphics by using a pad. In stepST5, the data processed in the individual steps ST4, ST7, and ST8 areprocessed in the same manner by using the single device driver. In stepST6, the processed data is sent to a system, such as an OS, in whichfurther processing is performed on the data to be displayed on thescreen.

As stated above, the coordinate data supplied from the circuit shown inFIG. 2 is processed by the device driver according to the flow chart ofFIG. 3. Thus, absolute coordinates, such as for characters, can be inputby using the pad-type first input device 2, while relative coordinatesfor vertically scrolling or tracking the display screen (window) of, forexample, a word processor or a spreadsheet, can be input by using thestick-type second input device 3. Further, relative coordinates fortracking a cursor (pointer) can be input by using the mouse-type thirdinput device.

In particular, since the absolute coordinate data from the pad-typesensor 2 a and the relative coordinate data from the stick-type sensor 3a are processed in the single device driver in the same data format, thefollowing type of processing can be easily executed. For example, a userstarts to input characters or graphics by using the pad-type sensor 2 aand stops halfway through. Then, by using the stick-type distortionsensor 3 a, the user moves the cursor to the position at which the userstopped writing, and inputs the position. Accordingly, the user is ableto continue writing the characters or graphics by using the pad-typesensor 2 a without losing track of the input position.

The personal computer system of the present invention is not limited tothe foregoing embodiment. For inputting relative coordinate data,another type of input device, such as a trackball, may be used. AlthoughID information is added to part of the relative coordinate data format,it may be added to the absolute coordinate data format, which may besuitably modified according to the format type.

As is seen from the foregoing description, the present invention offersthe following advantages. Different types of input devices can be usedsimultaneously without the need for a switching operation. Thisadvantage is effective particularly when absolute coordinate data, suchas characters, is input by a finger or by a pen using a pad-type inputdevice. In this case, even if the user lifts the finger or the pen fromthe pad and loses track of the input position, relative coordinate datacan be input by using a different type of input device without having toperform a switching operation for the input devices. As a result,characters can be input correctly.

1. A personal computer system comprising: a plurality of different typesof coordinate input devices; an output means for outputting a signalfrom each of said coordinate input devices, the output means configuredto embed an identifier in the signal that identifies one of thecoordinate input devices; and a processing means for alternating betweenthe signals from said coordinate input devices as the signals aretransmitted to the output means, said signals consisting of a first anda second data stream of at least three bytes or six bytes; a buffercoupled to the processing means that receives data from the first inputdevice and the second input device such that the coordinate inputdevices may be used simultaneously.
 2. A personal computer systemcomprising: a first input device; a second input device, said secondinput device performing a detecting operation in a manner differing fromsaid first input device; and an output device configured to send anoutput signal from said first input device or said second input deviceor from said first input device and from said second input device in atleast a three byte data stream or a six byte data stream, whereby saidoutput device combines signals received from the first input device andthe second input device in an alternating sequence wherein the firstinput device comprises a touch pad comprising an absolute pointingdevice and a relative pointing device.
 3. A personal computer systemaccording to claim 2, wherein said first input device outputs absolutecoordinate data and/or relative coordinate data, and said second inputdevice outputs relative coordinate data.
 4. A personal computer systemaccording to claim 2, wherein said first input device is a pad-typeinput device disposed closer to an operator than said keyboard inputdevice, and said second input device is a stick-type input devicedisposed between keys of said keyboard input device.
 5. A personalcomputer system comprising: a first input device; a second input devicethat differs from the first input device; an output means for outputtingoperation signals from said first input device and from said secondinput device in a variable length signal format; a processing unit thatalternately selects operational signals from said first input device andfrom second input device in response to an operation of said first inputdevice and said second input device; a buffer coupled to the processingunit that receives relative data from the first input device and thesecond input device; wherein said output means adds an identifier to aselected portion of the operational signal that distinguishes the inputdevices; wherein said first input device outputs variable information onX, Y, and Z three-dimensional coordinates, and said second input deviceoutputs variable information on X and Y two-dimensional coordinates, andwhen said second device is used, said identifier is added to aZ-information field of the signal format output from said output device;and wherein said output device generates six-byte absolute coordinatedata and supplies it to said processing unit in response to the variableinformation on the X, Y, and Z three-dimensional coordinates suppliedfrom the first input device, and said output device converts at leastthree-byte displacement data into six-byte data in response to thevariable information on the X and Y two-dimensional coordinates suppliedfrom the second input device, and said identifier is added to aZ-information field of the converted six-byte data.
 6. A personalcomputer system according to claim 5, wherein individual byte fields ofthe six-byte data supplied from said output device to said processingunit respectively indicate said identifier, X count information, X countand button information, Y count and button information, Y countinformation, and Z count information, and wherein the Z-countinformation becomes variable in accordance with an operation of saidfirst input device in response to the variable information supplied fromsaid first input device, and the Z-count information becomes fixed inresponse to the variable information supplied from said second inputdevice.
 7. A personal computer system comprising: a first input device;a second input device that differs from the first input device; anoutput means for outputting operation signals from said first inputdevice and from said second input device in a variable length signalformat; a processing unit that alternately selects operational signalsfrom said first input device and from second input device in response toan operation of said first input device and said second input device; abuffer coupled to the processing unit that receives relative data fromthe first input device and the second input device; wherein said outputmeans adds an identifier to a selected portion of the operational signalthat distinguishes the input devices; and wherein said output devicecomprises a switching portion for switching between a path forconverting the variable information obtained from said second inputdevice into the six-byte and a path for outputting the variableinformation as at least a three-byte data.
 8. An input devicecomprising: an input/output port; a first pointing device coupled to aninput of the input/output port; and a second pointing device coupleddirectly to the input of the input/output port; wherein the input/outputport has a single output channel through which data is transferred fromthe first pointing device and the second pointing device to a driverthat resides on a host; and wherein said first pointing device and saidsecond pointing device can transmit a fixed length data stream of atleast three bytes and at least one of said first pointing device andsaid second pointing device can transmit a fixed length data stream ofsix bytes.
 9. The input device of claim 8 wherein the first pointingdevice comprises a touch pad.
 10. The input device of claim 8 whereinthe second pointing device comprises a pointing stick and wherein saidfirst and said second pointing devices transmit data in a predeterminedbit sequence.
 11. The input device of claim 9 wherein the secondpointing device comprises a pointing stick.
 12. The input device ofclaim 11 wherein the input/output port comprises a controller forselecting an output from the touch pad and the pointing stick at a ratethat allows a user to control an on-screen movement of a cursor throughthe touch pad and the pointing stick simultaneously.
 13. The inputdevice of claim 8 wherein the input device comprises a dual pointingdevice, the first pointing device comprises a first relative pointingdevice integrated with an absolute pointing device, and the secondpointing device comprises a second relative pointing device.
 14. Theinput device of claim 13 wherein the second pointing device furthercomprises a format converter configured to send identifying data to thedriver that distinguishes the first pointing device from the secondpointing device.
 15. The input device of claim 8 wherein the firstpointing device is directly coupled to the second pointing device. 16.The input device of claim 8 wherein the single output channel is aserial port capable of sending and receiving data from a processor. 17.A dual pointing device used to control a cursor in a computercomprising: a port; a format logic coupled to the port, the format logicconfigured to transmit a data stream in lengths of three and more bytes;a touch pad comprising a first relative pointing device and an absolutepointing device coupled to the format logic; a stick comprising a secondrelative pointing device coupled to the format logic; and the firstrelative pointing device and the second relative pointing device eachcomprising a cursor control device in which a movement of a cursor onthe screen correlates to a movement detected by the first relativepointing device or the second relative pointing device; wherein theformat logic is configured to embed identifying data in the data streamin response to a command received from the computer, the identifyingdata distinguishing the stick from the touch pad, and the port comprisea single channel through which data is transmitted to the computer; andwherein the format logic is configured to transmit data in fixed lengthsof at least three and six bytes.
 18. A dual pointing device used tocontrol a cursor in a computer comprising: a port; a format logiccoupled to the port, the format logic configured to transmit a datastream in lengths of three and more bytes; a touch pad comprising afirst relative pointing device and an absolute pointing device coupledto the format logic; a stick comprising a second relative pointingdevice coupled to the format logic; and the first relative pointingdevice and the second relative pointing device each comprising a cursorcontrol device in which a movement of a cursor on the screen correlatesto a movement detected by the first relative pointing device or thesecond relative pointing device; wherein the format logic is configuredto embed identifying data in the data stream in response to a commandreceived from the computer, the identifying data distinguishing thestick from the touch pad, and the port comprise a single channel throughwhich data is transmitted to the computer; wherein the format logic iscoupled to a buffer that stores relative data temporarily beforetransferring the relative data in lengths of three or more bytes to thecomputer; and wherein the format logic is coupled to a second bufferthat stores absolute data temporarily before transferring the absolutedata to the computer.
 19. A dual pointing device used to control acursor in a computer comprising: a port; a format logic coupled to theport, the format logic configured to transmit a data stream in lengthsof three and more bytes; a touch pad comprising a first relativepointing device and an absolute pointing device coupled to the formatlogic; a stick comprising a second relative pointing device coupled tothe format logic; and the first relative pointing device and the secondrelative pointing device each comprising a cursor control device inwhich a movement of a cursor on the screen correlates to a movementdetected by the first relative pointing device or the second relativepointing device; wherein the format logic is configured to embedidentifying data in the data stream in response to a command receivedfrom the computer, the identifying data distinguishing the stick fromthe touch pad, and the port comprise a single channel through which datais transmitted to the computer; wherein the format logic is coupled to abuffer that stores relative data temporarily before transferring therelative data in lengths of three or more bytes to the computer; andwherein the buffer delivers data in fixed lengths of at least threebytes or six bytes in response to an output from a switch controller.20. A method of processing data transmitted from a plurality of relativepointing devices integrated within a computer, comprising: detecting afirst movement on one of a plurality of relative pointing devices andgenerating a first data stream associated with an on-screen movement ofa cursor on a display of a computer; detecting a second movement on atouch pad, the touch pad comprising a relative pointing device and anabsolute pointing device; monitoring a port coupled to a device driverresident to the computer; embedding identifying data in the first datastream that identifies at least one of the plurality of relativepointing devices; transferring the first data stream in lengths of threeor more bytes to the computer through the port; identifying the sourceof the first data stream when the identifying data is decoded; detectinga second movement detected by an absolute pointing device to a seconddata stream associated with an on-screen position of the cursor on thedisplay of the computer; and transferring the first and the second datastreams in lengths of at least three bytes or six bytes to the computerthrough the serial port.
 21. The method of claim 20 further comprisingidentifying the source of the second data stream when the identifyingdata is decoded.
 22. A computer including a host coupled to a displayscreen and an operating system comprising: a touch pad comprising afirst relative pointing device and an absolute pointing device; a stickcomprising a second relative pointing device; the touch pad and thestick each outputting operation signals to control a movement of thecursor on the display screen, wherein the touch pad outputs signals in afirst format when operated as an absolute pointing device and a secondformat when operated as a relative pointing device; a format convertercoupled to the touchpad and the stick, wherein the format converterreceives the operation signals and outputs a data stream of operationsignals in the same format for the touchpad and for the stick, whereinthe same format is one of the first format or the second format andwherein the format converter embeds identifying data in the data streamthat distinguishes the stick from the touchpad; a port providing asingle channel through which data from the format converter istransmitted to the host; and a mouse connected to the host; the hostincluding a device driver, the device driver receiving the convertedoperation signals in the same format from the touchpad and the stick andreceiving operation signals from the mouse, the device driver serving asa single device driver for shared processing of signals from both thetouchpad and stick and from the mouse; wherein the signals processed bythe device driver undergoes further processing by the operating systemto control cursor movement on the display screen.
 23. An input devicecomprising: an input/output port; a first pointing device coupled to aninput of the input/output port; and a second pointing device coupled tothe input of the input/output port; wherein the input/output port has asingle output channel through which data is transferred from the firstpointing device and the second pointing device to a driver that resideson a host; and wherein said first pointing device and said secondpointing device can transmit a fixed length data stream of at leastthree bytes and at least one of said first pointing device and saidsecond pointing device can transmit a fixed length data stream of sixbytes.